xref: /OK3568_Linux_fs/u-boot/doc/README.plan9 (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunPlan 9 from Bell Labs kernel images require additional setup to pass
2*4882a593Smuzhiyunconfiguration information to the kernel.  An environment variable named
3*4882a593Smuzhiyunconfaddr must be defined with the same value as CONFADDR (see mem.h).
4*4882a593SmuzhiyunUse of this facility is optional, but should be preferable to manual
5*4882a593Smuzhiyunconfiguration.
6*4882a593Smuzhiyun
7*4882a593SmuzhiyunWhen booting an image, arguments supplied to the bootm command will be
8*4882a593Smuzhiyuncopied to CONFADDR.  If no arguments are specified, the contents of the
9*4882a593Smuzhiyunbootargs environment variable will be copied.
10*4882a593Smuzhiyun
11*4882a593SmuzhiyunIf no command line arguments or bootargs are defined, CONFADDR is left
12*4882a593Smuzhiyununinitialized to permit manual configuration.  For example, PC-style
13*4882a593Smuzhiyunconfiguration could be simulated by issuing a fatload in bootcmd:
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun  # setenv bootcmd fatload mmc 0 $confaddr plan9.ini; ...; bootm
16*4882a593Smuzhiyun
17*4882a593SmuzhiyunSteven Stallion
18*4882a593SmuzhiyunJune 2013
19